<!DOCTYPE html>
<title>CSSOM Test: Chrome crash when modifying rules with @layer</title>
<link rel="help" href="https://crbug.com/1499277">
<link rel="author" title="Steinar H. Gunderson" href="mailto:sesse@chromium.org">
<style id="s">
.x {
  transition: color 0.5s;
  @layer warning {
    :first-child { }
    :last-child { }
  }
}
</style>
<p>Test passes if it does not crash.</p>
<script>
document.body.offsetTop;
s.sheet.cssRules[0].style.transitionDuration = '1s';
</script>

